Recently, there’s been a growing wave of startups and products appearing that are bringing 3-D virtual worlds to the browser. These include Vivaty, Google’s Lively project, and the Electric Sheep Co.’s WebFlock. And I’ve seen a few stealth companies working the same vein.

None of these are as fully featured or immersive as Second Life, which requires a separate desktop client download. But it may not matter because a good-enough experience available via standard browsers may eventually qwn Second Life. Linden Lab, which operates Second Life, is working with IBM and others to make virtual worlds interoperable with each other. Still, for the most part, they don’t play nicely with the Web.

Last week I caught Linden Lab founder Philip Rosedale on video at Fortune’s Brainstorm conference in Half Moon Bay, and asked him if Second Life is threatened by browser-based virtual worlds. In the video above, he argues that the browser is not yet ready to deliver the type of experience that you can get in Second Life. He does acknowledge that virtual worlds need to be opened up and standardized. But he doesn’t see the browser as a viable alternative to client-based virtual worlds any time soon.

Is he right, or is he in denial

My two cents: Rosedale is in denial. Yes, I am biased, having invested in Hangout.net, coming soon to a room near you (in September)…